Adjustable screw clamp for concrete molds



April 15 1924. 1,490,284

'J. A. M LEOD v ADJUSTABLE SCREW CLAMP FOR CONCRETE MOLDS Filed Dec. 30. 1922 Patented Apr. 15, 192 l JAMES A. meme or new HAVEN, ocnnnorrour.

' nniusrnnnn sonnw QLAMB non. ooncnn'rn MoLDsL Application filed December 30,1822. Serial No. 609,835.

To all whom it may concern:

Be it known that 1, JAMES A. NAoLnon, a citizen of the United States, residing at New Haven, in the county of New Haven a andtitate of 'Connecticuhhave invented a new and useful Improvement in Adjustable Screw Clamps for Concrete Molds; and I do hereby declare the following, when taken in connection with the accompanying drawingsand the characters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawapplication, and

-My invention relates to'an improved ad-' justable screw-clamp for concrete molds, the object being to greatly simplify andcheapen the installation of cast concrete work, with particular reference to the maximum salvaging of the lumber usedin the molds.

With these ends in view, my invention consists in an adjustable screw-clamp for concrete molds, the said clamp consisting so of a one-piece rod bent to form a shank provided at one end with a hand-grip adjacent to which it is furnished with a plurality of transverse perforations for the reception of an abutment-pin and a washer positioned thereby, threaded.

In carrying out my invention, as herein shown, my improved clamp is made from a. single piece of rod-stock and comprises a shank 5 having its outer end formed with an integral hand-grip 6 and, its inner end pointed and provided with standard woodscrew threads 7. The hand-grip end of the shank 5 is formed with a plurality of transverse perforations 8 for the reception in different positions of aremovable abutment,- pin 9 forming an abutment for a washer 10, which is shifted upon the shank according to the distance between the oppositely-located mold-boards 11 and 12 of the demountable mold, which, as shown, also comprises three corresponding, transversely-arranged spacers 13. The number of the transverse perforations 8 will be varied according to the desired range of adjustment. If prescrew-threads and pins. The washers serve and having its opposite end i'erred, the threaded 31 inner end of the shank may be provided with a machine screw-thread 14L to receive a nut l5, as shown in Fig. 3. a

in using my improved adjustable screw-. clamp, the mold-boards 11 and 12, forming the opposite walls or" the mold, are first installed, and the spacers 13 inserted between them. The screw-clamps are then inserted into the mold-boards through one or the otherthereot, as the case may be, and at right angles thereto.- The abutment-pin 9 and its washer 10 of each clamp are now adjusted, as called for by the distance between the two moldboards, and the length of the shanks of the clamps, which are now manually turned by their hand-grips to draw the mold-boards firmly against the ends of the spacers, thepurchase being provided by the to prevent the pins from being embedded in the wood and to reduce friction. The concrete, whatever its specific. character, is now poured and allowed to harden, after which the screw-clampsmay be readily removed "for the removal or re-positioning of the mold-boards, and their spacers, which may be used over and over again. The modified screw-clamp shown by Fig. 3 is peculiarly adapted for use with sheet-metal moldpieces, which may be used in place of wood, if referred.

By my improved screw-clamp I am able to carry on the work oi'casting concrete with the minimum amount of labor and expense, the salvage value of the lumber used in the molds being practically one hundred per cent. 1 am aware that a screw-clamp for concrete molds, consisting of a rod bent to form a straight shank with a hand-grip at one end thereof, the shank beingthreaded at its outer end, and provided at itshandend with a fixed washer, is old, and I do not claim such a construction broadly, but only myparticular construction, in which the hand-grip end of the shank is vprovided with a plurality of transverse perforations for the interchangeable reception of a pin to hold asliding washer at any predetermined position within the range of the said holes. I

I claim:

In an adjustable screw-clamp for concrete molds, the combination with a one-piece rod bent to form a straight shank with a Mind grip ofisetting from one end thereof, the hand gfifi end of thesha'nk havinga pluralit 'y of pa'ceGfi t'fansverse perforations and the outer end of the shank beingthreaded; 'of'a sliding washeri located upon the per-M forated end of thesai'd shankfend a 'pin interchangeable in the i said perforations for locating the "washerupon the shank in any I predetermined 'positi'on fihereon within the v 0 range of the said perforations, whereby the washer may be positioned upon the shank as required by the worki in' hand.

In testimony Whreofi-I hatvesigned this specification 1n the presence of two subscribing witnesses.

7 JAMES A. MAoLEOD.

Witnesses:

' FREDEBIOG. EARLE,

MALCOLM P. NIoHoLs. 

